The smooth muscle of the urinary bladder and large bowel is controlled by the sympathetic and parasympathetic divisions of the autonomic nervous system. In the proposed project, we will utilize electrophysiological and micropharmacological techniques to examine the central and peripheral autonomic mechanisms involved in this control. We are interested not only in the neuronal mechnisms which are present in the normal adult animal, but also in the emergence of these mechanisms during development and in their alteration following damage to the nervous system. We will study: (1) the intersegmental and supraspinal mechanisms which coordinate activity in excitatory and inhibitory pathways to these organs, (2) the role of the monoamines norepinephrine and 5-hydroxytryptamine and the amino acids in bulbospinal and spinal inputs to lumbar and sacral autonomic nuclei, (3) the organization of spinal somato-vesical and somato-colonic reflexes and changes in these reflexes during postnatal development and after spinal cord transection, (4) the role of peripheral ganglionic facilitatory and inhibitory mechanisms in regulating the neural input to the bladder and colon, (5) the importance of ventral root afferent fibers in the coordination of a lumbosacral autonomic reflexes, and (6) the organization of cardiovascular reflex pathways to the bladder and bowel. It is anticipated that this work will lead to a clearer understanding of the mechanisms underlying sympathetic-parasymapthetic and somato-visceral interactions in the regulation in excretory function.